From: Steven Whitehouse Subject: Re: [RFC v4+ hot_track 03/19] vfs: add I/O frequency update function Date: Mon, 05 Nov 2012 11:07:05 +0000 Message-ID: <1352113625.2705.10.camel@menhir> References: <1351485061-12297-1-git-send-email-zwu.kernel@gmail.com> <1351485061-12297-4-git-send-email-zwu.kernel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linuxram@linux.vnet.ibm.com, viro@zeniv.linux.org.uk, david@fromorbit.com, tytso@mit.edu, cmm@us.ibm.com, wuzhy@linux.vnet.ibm.com, wenqing.lz@taobao.com To: zwu.kernel@gmail.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:19831 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751721Ab2KELHx (ORCPT ); Mon, 5 Nov 2012 06:07:53 -0500 In-Reply-To: <1351485061-12297-4-git-send-email-zwu.kernel@gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi, On Mon, 2012-10-29 at 12:30 +0800, zwu.kernel@gmail.com wrote: > From: Zhi Yong Wu > > Add some util helpers to update access frequencies > for one file or its range. > > Signed-off-by: Zhi Yong Wu > --- > fs/hot_tracking.c | 179 ++++++++++++++++++++++++++++++++++++++++++ > fs/hot_tracking.h | 7 ++ > include/linux/hot_tracking.h | 2 + > 3 files changed, 188 insertions(+), 0 deletions(-) > > diff --git a/fs/hot_tracking.c b/fs/hot_tracking.c > index 68591f0..0a7d9a3 100644 > --- a/fs/hot_tracking.c > +++ b/fs/hot_tracking.c > @@ -172,6 +172,137 @@ static void hot_inode_tree_exit(struct hot_info *root) > } > } > > +struct hot_inode_item > +*hot_inode_item_find(struct hot_info *root, u64 ino) > +{ > + struct hot_inode_item *he; > + int ret; > + > +again: > + spin_lock(&root->lock); > + he = radix_tree_lookup(&root->hot_inode_tree, ino); > + if (he) { > + kref_get(&he->hot_inode.refs); > + spin_unlock(&root->lock); > + return he; > + } > + spin_unlock(&root->lock); > + > + he = kmem_cache_zalloc(hot_inode_item_cachep, > + GFP_KERNEL | GFP_NOFS); This doesn't look quite right... which of these two did you mean? I assume probably just GFP_NOFS > + if (!he) > + return ERR_PTR(-ENOMEM); > + > + hot_inode_item_init(he, ino, &root->hot_inode_tree); > + > + ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM); > + if (ret) { > + kmem_cache_free(hot_inode_item_cachep, he); > + return ERR_PTR(ret); > + } > + > + spin_lock(&root->lock); > + ret = radix_tree_insert(&root->hot_inode_tree, ino, he); > + if (ret == -EEXIST) { > + kmem_cache_free(hot_inode_item_cachep, he); > + spin_unlock(&root->lock); > + radix_tree_preload_end(); > + goto again; > + } > + spin_unlock(&root->lock); > + radix_tree_preload_end(); > + > + kref_get(&he->hot_inode.refs); > + return he; > +} > +EXPORT_SYMBOL_GPL(hot_inode_item_find); > + > +static struct hot_range_item > +*hot_range_item_find(struct hot_inode_item *he, > + u32 start) > +{ > + struct hot_range_item *hr; > + int ret; > + > +again: > + spin_lock(&he->lock); > + hr = radix_tree_lookup(&he->hot_range_tree, start); > + if (hr) { > + kref_get(&hr->hot_range.refs); > + spin_unlock(&he->lock); > + return hr; > + } > + spin_unlock(&he->lock); > + > + hr = kmem_cache_zalloc(hot_range_item_cachep, > + GFP_KERNEL | GFP_NOFS); Likewise, here too. Steve.